Search Publications
Observational constraints on Gauss-Bonnet cosmology
Benetti, Micol; Alcaniz, Jailson S.; Capozziello, Salvatore +2 more
We analyze a fully geometric approach to dark energy in the framework of F(R,𝒢) theories of gravity, where R is the Ricci curvature scalar and 𝒢 is the Gauss-Bonnet topological invariant. The latter invariant naturally exhausts, together with R, the whole curvature content related to curvature invariants coming from the Riemann tensor. In particul…
Foreground contribution to the inferred cosmological parameters from Planck
Vincent, Aaron C.; Wibig, Tadeusz; Wolfendale, Arnold W.
Previous analyses of cosmic microwave background (CMB) measurements [T. Wibig and A. W. Wolfendale, Mon. Not. R. Astron. Soc. 360 (2005) 236, arXiv:astro-ph/0409397; Mon. Not. R. Astron. Soc. 448 (2015) 1030, arXiv:1507.0677.] have revealed contamination by areas of high cosmic ray activity in the Milky Way. Here, we update studies, looking at the…
Imaging cosmic polarization rotation
Contaldi, Carlo R.
We introduce a method to isolate the contribution of parity-violating modes to the peak constrained correlation function. This method can be used as a local estimate of polarization rotation. We test this method using simulations and by applying it to Planck maps [P. A. R. Ade et al., arXiv:1502.01589 astro.ph.co]. We obtain a constraint on the mo…
Observational hints of a pre-inflationary scale?
Gruppuso, A.; Sagnotti, A.
We argue that the lack of power exhibited by cosmic microwave background (CMB) anisotropies at large angular scales might be linked to the onset of inflation. We highlight observational features and theoretical hints that support this view, and present a preliminary estimate of the physical scale that would underlie the phenomenon.
Updated reduced CMB data and constraints on cosmological parameters
Cai, Rong-Gen; Guo, Zong-Kuan; Tang, Bo
We obtain the reduced CMB data {lA, R, z∗} from WMAP9, WMAP9+BKP, Planck+WP and Planck+WP+BKP for the ΛCDM and wCDM models with or without spatial curvature. We then use these reduced CMB data in combination with low-redshift observations to put constraints on cosmological parameters. We find that including BKP results in a h…
General dissipative coefficient in warm intermediate inflation in Loop Quantum Cosmology in light of Planck and BICEP2
Videla, Nelson; Herrera, Ramón; Olivares, Marco
In this paper, we study a warm intermediate inflationary model with a general form for the dissipative coefficient Γ(T, ϕ) = CϕTm/ϕm-1 in the context of Loop Quantum Cosmology (LQC). We examine this model in the weak and strong dissipative regimes. In general, we discuss in great detail the characteristics of this …
BICEP2 constrains composite inflation
Channuie, Phongpichit
In light of BICEP2, we re-examine single field inflationary models in which the inflation is a composite state stemming from various four-dimensional strongly coupled theories. We study in the Einstein frame a set of cosmological parameters, the primordial spectral index ns and tensor-to-scalar ratio r, predicted by such models. We conf…
The Planck Mission: Recent Results, Cosmological and Fundamental Physics Perspectives
Burigana, Carlo; Gruppuso, Alessandro; Natoli, Paolo +1 more
We provide a description of the latest status and performance of the Planck satellite, focusing on the final predicted sensitivity of Planck. The optimization of the observational strategy for the additional surveys following the nominal 15 months of integration (about two surveys) originally allocated and the limitation represented by astrophysic…